SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87dfb6ad4d68432dcd58a63b9146d1944833b023d66c732617f88e4522825f27' 
  AND token = 'vEVFwE7qIePZIwGCL85U8Pp+DDQGqJKD1XAweW+oy2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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