SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65d67d0fe79bf372aa7a2135fd175f9c658e3a8cde1784a82bbc85c4a7f913f4' 
  AND token = 'j+KYC0j/A7LRCiTX+yQIKoCiAtbzcdL2Vwzwvq9zdWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00067

JSON explain

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