SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62e75e91e1d3e3a4e990d4a49178822a83a8200f294c82c3d6bd495e6ffdf8ce' 
  AND token = 'VmODCkWaeCCJB36Am03Fa6JR3CWWiR09kzxABKo8wyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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