SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35cac9c19f2f3f5d9e687c41e3e3f60aa33152c9454249313b641430046119e3' 
  AND token = 'Ej+WHFT7/+BLJJGZwA96Ty4+EP7RA62F+eFla2ROegw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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