SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '363de29cc75bc98367cbd8dd3c29ebe186935254351f3fc2147dec5be5ca9a22' 
  AND token = '+IXynpfAub/cQxCviiYI2pI4KQ6G+A/sqG/mvVPjWeo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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