SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd188522df519f48b4c844d3fd4480e6101f3eefe9527f931c966e3d1f46ebcc' 
  AND token = 'MGbJeygjjAhJuONhwGVweL05ZAH4/VxD5V6q44r08TY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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