SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd628511b3a092b29c614d04b69ebd31af27adabb1e4858017560edeee3af087d' 
  AND token = 'vFaQ2abx0AJmhEbctgEQBpzHgBa/Oq888GJIVBuMjjk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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