SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a00aa7766659ee54f83bf9446163495dea136d529a0be38540c80d3a1256cb02' 
  AND token = 'AeIUU2lR7iGO8hvOyMDsq31rRocW4Oalm1NTI1LYvSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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