SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2e8e34472531a0bb3345779e7e52ecca2753ca68a36ac195faebad4ffb1f2d93' 
  AND token = 'L1Z6O0LqlOA9lKpEN3ZJA/ah/Jua2oEMBgghdHSqDl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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