SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6f9e5002a6e091fb3aa3dd14934e50bdf4142abade2cf8bafc58d97c10d37ffc' 
  AND token = 'FI8i4iqaInCNWSqdc4RlaBEDWOfkpiDY/wjNtCIgSa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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