SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '054b6bfa49efe04485ed541c77d2bead34fde1dab4b2aafeb23950f8124b6b02' 
  AND token = 'Byyayu7Mx4yZr/sxiEl/D5DQ+NwgyRjD7a7Ke+So/g0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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