SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd111959c44c2e8fc4f16738f57a754f446b2ddd2ddafdf32150e18d8f48af36' 
  AND token = 'O1yG9dnDDG4HdmkDqzDrb79gy4PTKmk6MxE9+JAxMBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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