SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd18e224724eff20f7e4a2c0d0ec26fcea6419dd0bde2025ecdbc5aa03697eefe' 
  AND token = 'MrMdusdyvgtEsdJ8egxdwnTdW5xi/RrzkblXcCcTUrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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