SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd659243293646127389468298d2fd953d7ab00ded85ce52c7906bfba16d33f' 
  AND token = 'T3LWDnczihqlvrGFbtZm5/tfi94aE3GbNGPC5dLqu24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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