SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0869136412b926343f316827a0d4b4089bd3078ecd50c90e1ccad60975819a3' 
  AND token = 'ixjIuHcc63vx4v6Bc2A4IAfHEs69RPyE9Cmodlfwqc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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