SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2ad5bbccecef81e25d162ba19e29162b2a638fec50a3efc88fc03ac6e51d955' 
  AND token = 'GgR+ry1h/wVH63xNTVuWyAn0dAEMLXjvYpGQHci2m8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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