SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f085e985c193d092975ec6c88e42352b6feea478681bee7722fd0661f532d97' 
  AND token = 'C8Dv2eFHkR6nVYGDrZIejNeKJpnsBPv1LB8Y90SxjKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}