SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9557e41428eb19a241b243ca859b7de3852b77e7055bb22a1dbd8b3fafd443e3' 
  AND token = 'ykssyO96DdvrNAcarHxXNUSyjqXrxAidAuiK7g2+qs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}