SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9d1f6a5fabe0b1aa7e2026831324b6eb2b2411827d2115d47946304597294957' 
  AND token = 'NiLnCnCvF4fiONlR9OFaYq3AGLodbqYC4a90Pl9PkPs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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