SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9302a9108c33f9f449048689401de3999fbaa895485509002b8d290a355330ac' 
  AND token = 'G7ggByXvJkPaEVgacfD6k2n9UFlsqCvgTx1uRg3UCM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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