SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b68becf17316d94e4074b8b69d5783462096f28aa0d14051ff48122e6839bb99' 
  AND token = 'n4fWWhdY+kQCjdn4LdArvgHHYwr+AGPkVPGKjNhhLEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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