SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd03cd09aebee552b8b33dd48ede6f7e317228cab7fd06923faca259d0994445' 
  AND token = 'LkBerevEyBskddWCX3OFUEZD4N8H0ul4giMyjOxd0sk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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